Driving device for the music bands or strips of pneumatic music machines



C. HITZEGRAD. DRIVING DEVICE FOR THE MUSIC BANDS 0R STRIPS 0F PNEUMATIC MusIc MACHINES,

APPLICATION FILED A'UG.30, I920.

1,436,879. Patented Noir. 28, 1922.

Patented Nov. 28, 1922.

UNITED STATES PATENT OFFICE.

CARL HITZEGRAD, OF BBEMEN, GERMANY, ASSIGNOR TO TONFILM-GESELLSCHAFT M. B. H., OF BREMEN, GERMANY.

DRIVING DEVICE FOR THE MUSIC BANDS OR STRIPS 0F PNEUMATIC MUSIC MACHINES.

Application filed August 30, 1920. Serial No. 407,043.

To aZZ w/ama it may concern:

Be it known that I CARL HITZEGRAD, a citizen of the German epublic, residing at Bremen, Germany, have invented certain new and useful Improvements in Driving Devices for the Music Bands or Strips of Pneumatic Music Machines, of which the following is a specification.

The music-sheets or strips in pneumatic music machines are usually guided over the suction bar and driven through being wound up on a cylinder revolved from any source of energy. This drive has the inconvenience, particularly if the music-sheets or strips are very long, that in consequence of the uniform angular velocity of the receiving cylinder the unwinding of the strip or sheet accelerates with the increase of the diameter of the said receiving cylinder. This inconvenience makes itself felt very much with musical pieces of a certain length, for example with overtures and it becomes almost insufferable for music played as accompaniment for cinematographic displays. The music for cinematographs requires always very long music-sheets or strips and it is essential that these music-sheets are unwound with absolute uniformity.

This invention has for its object to obviate the said. inconvenience by using frictional drive. The frictional drive which has already been used technically in connection with conveyor bands has never been applied to pneumatic music machines. The invention consists in this that the part of the music-sheet or strip between the delivery cylinder and the receiving cylinder is directly acted upon by friction cylinders or rollers which are revolved independently of the receiving cylinder. The receiving cylinder merely serves for tightening the music band upon the suction bar.

According to this invention the music strip is further guided between a conveying cylinder and between two friction roll.- ers, only one of these three parts being driven.

In the accompanying drawings the preferred form of embodiment of my invention is shown.

Fig. 1 is a diagrammatic side elevation of the driving device.

Fig. 2 is a plan view of Fig. 1.

The music strip a is unwound, in the well known manner, from the delivery cylinder,

guided over the suction bar o of the pneumatic music machine, and wound up on the receiving cylinder (Z. The conveying of the music strip a. is effected through conveying means which act directly upon said strip before the same is wound up on the receiving cylinder 02?. These conveying means consist of a friction cylinder 6 driven from the source of energy of the pneumatic machine and acting upon said strip a through friction in combination with other parts which will be more particularly described hereafter.

The receiving cylinder d is rotated from the mechanism of the music machine in the usual way for the purpose of tightening the music strip and for winding the same up for future use and in such a manner that through this revolution of the receiving cylinder the music strip is not unwound.

In order to effect an elastic conveying of the music strip and in order to prevent the damaging of the strip or a deformation of the same, the driving device shown in Figs. 1 and 2 isconstructed in such a manner that the conveying of the music strip is not effected rigidly but elastically, whereby further an absolutely uniform conveying is obtained. WVith this object in view the music strip a (Figs. 1 and 2) is pressed against the conveying cylinder 6 by means of friction rollers f, f. The axles of said rollers f, f are rotatably mounted in supporting arms 9, g which are pivotally mounted upon pivots la. carried by levers i, 2'. These levers i, i are pivotally mounted u on pivot bolts 70, 7c of the base plate 1. prings m, m mounted between the base plate and said levers 2', i serve for pulling the levers z', z" against the base plate Z and consequently the friction rollers f, f against the lower surface of the music strip a. The rollers f, f exert a uniform pressure upon the music sheet or strip a; but are adapted to yield whereby the uniform advance of the music strip is ensured, damaging of the same being prevented. As each lever z, i is pivotally mounted independently of the other and influenced through a separate spring m, m the friction rollers f, f at one side of the machine can give way independently of the friction rollers at the other side of the machine so that the conveying of the music strip is not at all rigid.

The conveying means, rollers, cylinders or Q 1 ,es

the like can be of any convenient construction. They are preferably covered with india-rubber or with a protecting cover so that they exert a soft uniform pressure upon the music strip which is however sufficient to convey said strip. The cylinders e are preferably mounted so that they can be raised or lowered to facilitate the insertion of new music strips. These rollers can further have grooves, indentations or the like to facilitate the conveying of the music strip and to permit of the passage of eyes or similar insertions in said strip.

I claim 1. In mechanism for the purpose described, a conveying cylinder, independently mounted levers, pivotally mounted arms ar- 

